What's Hot: Excellent portable power for smartphones, built-in cables and easy to use.

What's Not: Doesn't have a lot of power for charging tablets.

Reviewed by Tong Zhang

A-solar is a portable battery company that offers solar powered chargers as well as AC-charged portable batteries. Their new Xtorm Power Bank 7300 (AL370) portable battery packs whopping 7300mAh power and can juice up a regular smartphone without breaking a sweat and even the extra large sized ones such as the Samsung Galaxy Note II with a relative ease. The battery can also charge tablets, but it functions only as top up for the tablets as it can only fill partial power on both Apple and Android tablets. The Xtorm is easy to carry on the road and it's certainly a good solution if you need to charge your phone, digital camera and other accessories while on the go.

Design

The Xtorm Power Bank 7300 comes in a brick style form with brushed aluminum front and a soft touch body. It has two integrated cables, one on each side and the end plugs tucked neatly into the groove made for them to sit flush with the battery. The built-in USB cable allows you to charge the Xtorm Power Bank 7300 battery and the micro USB cable lets you charge any mobile device with a standard micro USB connector. If your device doesn't have a micro USB charging port, the Xtorm battery has a standard USB charging port on the bottom for charging with devices such as iPhone and iPad models.

The Xtorm Power Bank 7300 measures 4.72 x 2.95 x 0.79 inches and it weighs 7.4 ounces. It's very easy to use and has only one control button on the front below the four LED lights. The button can turn on charging as well as check battery level. In case you have other devices to charge, the Xtorm Power Bank 7300 comes with a bag of adapters for Samsung phones, tablets, Sony Ericsson phones and Mini USB adapter. The battery comes with a stretchable USB cable and an AC adapter.

Features

The Xtorm Power Bank 7300 has a large Lithium-polymer battery that's 7300mAh in capacity. The large battery offers 1A output power via the built-in Micro USB cable and up to 2.1A power from the full USB port for charging your mobile devices. It can charge two devices at the same time, but the output can only charge two smartphones not a smartphone plus a tablet. We tested the battery with several smartphones and it charged everything easily. For the iPhone 5, the battery barely used 20-percent of its full power and it took 2.5-3 hours to fully charge the iPhone 5's empty battery. For the large Samsung Galaxy Note II, the battery used less than 40-percent of full power and charged the phone in 3 hours. We tested other Android smartphones and two smartphone charging at the same time, the Xtorm Power Bank 7300 charged all smoothly.

Since the Xtorm Power Bank 7300 can output 2.1A, we tested it with several tablets as well. The battery handled smaller sized tablets such as the Google Nexus 7 and Kindle Fire HD 7" than the larger 10.1" tablets at providing more power. The Xtorm Power Bank 7300 filled the Nexus 7 with more than 20-percent battery left to spare and it charged it in about 3 hours. With the iPad with Retina Display (4th gen), the Xtorm Power Bank 7300 dumped all its power to fill 43-45-percent of the iPad's battery life, and it took over 4 hours to charge from empty to full. Still that's better than the Samsung Galaxy Tab 10 which couldn't take any charge from the battery.

The Xtorm Power Bank 7300 comes with a built-in USB cable with which you can charge the battery via either a computer or an AC outlet. The battery can take 5V-1A input power and you can charge it using the included AC adapter or your phone's AC adapter. Charging via an Apple iPad AC block, the Xtorm Power Bank 7300 takes about 3-4 hours to fully charge. It takes longer charging it via a computer. The battery has power pass through, which means you can charge your phone/tablet at the same time charging the batter pack, but the batter doesn't have data pass through which means you can sync your device while charging via the battery even when the battery is plugged into your computer.

The built-in 4 LED lights come in very handy for check out power level. The last light flashes blue when the battery is at 0-20-percent power. The battery doesn't automatically charge when you plug in your mobile device, you must press the power button to turn on charging. Your device will wake up when the batter is fully charged and the battery has no other alert for a full charge. It does turn itself to sleep once the mobile device is fully charged.

Conclusion

There is a lot to like about the Xtorm Power Bank 7300 including its large capacity, the clean design, the built-in cables and the ability to charge two smartphones at once. The battery is super easy to use and it's compact enough to carry with you on the road. It works with smartphones, digital cameras, portable gaming devices and even tablets, though not all tablets work with the battery. The Xtorm Power Bank 7300 is excellent companion if you consistently need to charge your smartphone and it can provide some relief for your tablet as well. A-solar has shipping outles and online in Europe and ships their products worldwide.